Probably a admin.
On TmF servers they can change weapons on command.
a few days ago i was playing in teknogods mw3 isnipe knowing that you only get sniper classes after a while i started to notice that there was somebody using a normal gun i sstarted to hid and after every one was dead but me and him i started to look for him about a few seconds lateri found with a acr .....i was shocked and jeoulse also
...so my problem is how do i get that pls
Probably a admin.
On TmF servers they can change weapons on command.
There's a simple method that can be used to unlock all your custom classes even if it's blocked. ( Please note I said custom classes, not default. )
So reverse the game a bit and you should find it.